During the Second World War, Hull fair was stopped but many showmen were busy supporting the 'Fairs at Home'. Many showmen saw active service and it is with sadness that the World’s Fair reported the loss of many a young man during the war. It was only with the cessation of hostilities in 1945 that the fair reopened on Walton Street. The war years had seen the loss of the annual festivities and the fairground site had been requisitioned for military purposes.

However, in 1945 the authorities released the site temporarily in order that the battered city of Hull could celebrate their traditional festival. The fair opened on Thursday October 11th on the large front of Fossett’s circus and in his welcoming address the Lord Mayor of Hull, Councillor Nicholson declared "that if any place in the country was entitled to relaxation it was the battered city of Hull." The World’s Fair reporter stated that although everything was made to look as attractive as possible the fair was not yet up to the standards that had been set before the war. By 1947, the report in the showmen's newspaper was more optimistic that although the acreage of the site was still 13 compared to 14 acres in the 1930s the attractions on offer were the best that could be found on any fair in the country:

Throughout the fair the attractions represented the cream of the show world. In fact seeing everything so spick-and-span made me proud to be associated with the Showland.

The dawn of the Rock and Roll Age announced a new era for the fairground, taking it away from 1940s austerity where pre-war attractions had enjoyed a new wave of popularity. The 1950s was a time when popular culture began to establish itself as an ‘industry’, where new rides, music and changes in popular culture would once again be reflected on the travelling fairs. Youth cultures begin to emerge with rock and roll and the first signs of a direct competition to the fair can be seen. But the 1950s were again a golden, if somewhat brief period, as cultural themes were well represented on the fairground in the artwork of Edwin Hall and Fred Fowle, whose style became synonymous with the decade. Rides were renamed the rock and roll Speedway, the Cavalcade of Swing, Ben Hur and the Brooklyn Cake Walk of the 1900s was retitled the Rock 'n' Roll. The physical design of the rides became a feature of the name such as the Odeon style Waltzer with its vaulted column extension fronts reflecting more the age of 1930s cinema buildings in architectural style but renamed as the Ultra Modern Thrillers. Music and film were strong forces in popular culture and the fairground often plugged directly in to specific aspects. The development of sound systems played an important part in this, enabling the fairground to become a hot-spot of activity for those perhaps excluded from, but wanting to experience, the social arenas of listening to and partaking in rock and roll:

Some people can work a machine some people cannot — you have to work a machine with the music and you walk past and stop to listen to it — you can have two identical machines next to each other and one will take more money than the other because it’s the skill of the operator who has just got the knack with the music and how they work the machine. My cousin Henry could close a ground up with his Speedway and nobody else took any money — that's the showman's art. [Mrs Sandra Wright, interviewed January 2003.]

As Mike Hanna recalls in the Fairground Mercury, 'Rock and Roll, here at last was THE perfect fairground music!!' The fairground became a place to hang out — to hear records that might not be easily attainable — to experience the social nexus that was strictly preserved for young adults. Places for the new teen market were limited and the fairground was one arena where this new and forbidden music could be heard and enjoyed as portrayed in the film That'll be The Day. Walls of Death were repainted to reflect the American Biker culture as typified in The Wild One and American teen idols replaced the painted figures of Royalty on the Arks and Waltzers. Hollywood imagery was deployed by fairground artists such as Fred Fowle who was influenced by a range of influences including the B movie's and the artwork of the pulp novels:

I suppose it's a matter of keeping your eye open. Anything that was attractive I absorbed it. The daily press, magazines, — things hit you that look effective and you adapt it to the show work. One of the best inspirations is the national press and magazines. Plus advertising. [Interview with Fred Fowle, fairground artist cited in Weedon and Ward, Fairground Art, p. 207-208.]

Rides were physically developed or re-deployed for this purpose — Waltzers and Arks had gantries to 'hang out' on, Dodgem tracks were used temporarily to hold rock and roll dancing competitions — a ritual that made sure every who craved, and so partook in, a certain atmosphere would be present from the start. The shows became less innocent and more in keeping with the new age of sexuality as Arthur Stevens, a showman from Wales recalls:

The girls used to perform the striptease and the fan dancing and the dance of the seventh veils - they never did anymore than showing the breasts -that was the ultimate if they showed the breast and even then it was through a gauze - through a veil or through the fan. Today young girls walk around showing more on the streets than what we showed. Well I had about four or five boys in my performance and next door to me was young Lawrence Appleton and he had forty people come out, all young men. Well they'd come out and they'd go straight back in and obviously he was showing a lot more than he should have been. One particular day Past President Billie Whitelegg and Mr Albert who was the Chairman of the Western Section, had a complaint about him and I can always remember Mr Whitelegg's words he came to me and said "Arthur we've had a problem from the watch committee complaining about somebody's showing raw meat" and that's Billie's expression - the girl was showing too much - if you just stand and watch where the crowds go you can see who is showing it you know.

By the 1950s Hull Fair was bigger and although the civic opening remained at 12.00 p.m. on the 11th of October, the introduction of a fanfare of trumpets livened up the proceedings. The relationship between the Showmen’s Guild and the Council officials remained strong and was further consolidated in 1955 with the gift of a replica of the original fair charter to the Guild. Hull continued to be seen as the jewel in the crown of the Yorkshire fairs and the highlight of the showland season throughout the decade. In 1960, the Hull Chamber of Trade, whose members it claimed suffered a severe drop in business during the week of the fair, attempted to prevent the fair opening for two Saturdays. The Council vetoed this attempt, however, the document produced by the Chamber of Trade, stated that the fair only ran over two Saturdays when the 11th of the month fell on a Saturday, Sunday or Monday. The Chamber of Trade also claimed that the rent had to be increased to meet the additional charges of holding the fair over the week. Another interesting aspect of the report was the claim that Nottingham Goose Fair produced more profit than Hull Fair. Despite the protests, the 1960 fair was held over two Saturdays and during the annual dinner and dance, the Lord Mayor replied to the critics of the fair in the following speech:

As well as making us spend money, I am sure the Fair attracts many people to the town, who would not normally come. It has been suggested that our people are so unintelligent that they spend much more money at the Fair than they should do. I think the idea is very wrong and those who hold it must have a wrong idea of the Yorkshire character. I am sure that the Yorkshire people don’t spend money unless they know they can really afford it.